Any potential improvements in the input speed, comprehension and/or retention of information gained via reading would be clearly beneficial to a wide spectrum of users in many diverse applications.
It is believed that use may be made of the readers subconscious to enhance the recognised conscious reading mechanisms typically employed during the reading of books, computer screens, visual displays and so forth. Current means of increasing the quantity of information available to the reader have largely involved decreasing the font size to provide a greater quantity of text surface area. However, this technique fails to overcome the inherent limitations of the human eye, i.e. reducing the text font size below a certain level causes a significant reduction in readability.
Menus, layering, pop-up windows and so forth have been used single focal plane prior art displays as alternative means of enhancing the quantity of information available to the reader without making the display overly cluttered.
Although the use of menus and similar hierarchical display methods do enable the user to access the required information without the need for large display surfaces or undue display clutter, they reduce the viewer's situational awareness. Moreover, they require positive interaction by the user, which is not always practical or desirable and are unavoidably slower to use than continuously displayed information.
Multi-layer or multi-focal plane displays have been utilised to address the above difficulties whereby two or more display screens at least partially overlap, displaying information in two or more distinct focal planes. The viewer may thus focus on the individual screens to view the information displayed thereon without accessing a menu or needing to make significant head/eye movements to scan large display surfaces.
Research such as the Transparent Layered User Interfaces: An Evaluation of a Display Design to Enhance Focused and Divided Attention, Harrison et al, CHI 95 Conference (1995) examined the link of transparent displays on focused and/or divided attention.
Examples of focused attention include a computer software dialog box or warning message interrupting a user concentrating on a document, or part of a display screen being temporarily obscured by a drop-down menu.
Divided attention examples provided by Harrison et al include using a video display showing a colleague during collaborational work, were the participant's attention is shared between the colleague and the work in progress, e.g., a drawing or document.
Harrison et al considered cases of individuals needing to time-share two information items or ‘tasks’ (divided attention), and cases were individuals selectively attend to one task excluding the other (focused attention). However, no specific exploration is made of the potential benefit of the unfocused information item on an individual focusing on another information item/task.
Various means of simultaneously displaying and analysing large literary text is disclosed at the TextArc™ website http://textarc.org (15 Apr. 2002). The display techniques employed are highly unusual and innovative. In one embodiment, the entire text of a novel for example, is arranged in concentric spirals. Each successive line of the novel is written in miniature around the outside of the spiral, with frequently occurring words also being displayed in a larger font within the spiral arc. The frequency of occurrence within the document is denoted by the word's intensity or luminance, while its location is determined by the mean geometrical position between occurrences about the outer spiral. Additional displays of the text in a conventional form may be overlaid on the spiral arc representation, enhancing the pre-attentive possibilities for the viewer. As the viewer scrolls through the conventional text, the high frequency words are illuminated within the spiral, together with radial lines extending to each point in the spiral containing the word.
A viewer may thus see a measure of a word's significance, its interconnection to other words and its effective location within a document. The viewer is thus presented with exposure to the bottom up structure of the entire document and to a variety of interrelationships between the contents.
However, the combined/overlapping display obscures a portion of the text spiral arrangement. Furthermore, the sheer wealth of visual input in one focal plane may be distracting and hinder preattentive intake by the viewer.
Further prior art work by Ishii H et al, “Iterative Design of Seamless Collaboration Media”, Communications of the ACM (CACM), ACM, Vol 37, No. 8, August 1994, and the work described at the web sites http://web.media.mit.edu/˜ishii/TWS.html, and http://web.media.mit.edu/˜ishii/CB.html by the same authors discusses combination computer display/whiteboard-type transparent displays. The issue addressed by Ishii et al is creating a usable work space environment combining the benefits of a computer screen interface, a physical desktop and a dual sided transparent glass-board. The resultant system provides a display surface on which the images of collaborative workers appear to face the user whilst any text/drawing written by any of the collaborators/users automatically appears with the correct orientation on the combined display. This overcomes the problem of inversion caused by collaborating users writing on opposing sides of a common transparent panel. The meaning of facial gestures and body language nuances of the collaborators regarding particular items in the workspace screen may be easily discerned. However, again the display surface is essentially a single focal plane and thus does not take full advantage of the preattentive depth-related capabilities of the user, as described below.
The benefits of multi-layered viewing screens, in particular those utilising the technology described in the co-pending Patent Application Nos. NZ314566, NZ328074, NZ329130, PCT/NZ98/00098 and PCT/NZ99/00021 are gaining increasingly widespread recognition and acceptance due to their enhanced capabilities compared to conventional single focal plane displays.
The basic principle of known multi-focal plane displays is that the viewer consciously applies their attention to one of the focal planes individually or to a composite image found by the combination of images displayed on at least partially transparent screens.
Therefore, although the viewing experience may be enriched by the potential sense of depth provided by such composite displays, it has not been utilised thus far as a means of enhancing the reading/image assimilation speed of the viewer, nor of using the information displayed on one focal plane to improve the net effect on a user consciously viewing the display on a separate focal plane. Such improved effects could include improvements in comprehension, perception, retention, recall, interpretation and/or association with related information.
The manner in which human beings process visual information has been the subject of extensive and prolonged research in an attempt to understand this complex process. The term preattentive processing has been coined to denote the act of the subconscious mind in analysing and processing visual information which has not become the focus of the viewer's conscious awareness.
When viewing a large number of visual elements, certain variations or properties in the visual characteristics of elements can lead to rapid detection by preattentive processing. This is significantly faster than requiring a user to individually scan each element, scrutinising for the presence of the said properties. Exactly what properties lend themselves to preattentive processing has in itself been the subject of substantial research. Colour, shape, three-dimensional visual clues, orientation, movement and depth have all been investigated to discern the germane visual features that trigger effective preattentive processing.
Researchers such as Triesman [1985] conducted experiments using target and boundary detection in an attempt to classify preattentive features. Preattentive target detection was tested by determining whether a target element was present or absent within a field of background distractor elements. Boundary detection involves attempting to detect the boundary formed by a group of target elements with a unique visual feature set within distractors. It maybe readily visualised for example that a red circle would be immediately discernible set amongst a number of blue circles. Equally, a circle would be readily detectable if set amongst a number of square shaped distractors. In order to test for preattentiveness, the number of distractors as seen is varied and if the search time required to identify the targets remains constant, irrespective of the number of distractors, the search is said to be preattentive. Similar search time limitations are used to classify boundary detection searches as preattentive.
A widespread threshold time used to classify preattentiveness is 200-250 msec as this only allows the user opportunity for a single ‘look’ at a scene. This timeframe is insufficient for a human to consciously decide to look at a different portion of the scene. Search tasks such as those stated above maybe accomplished in less than 200 msec, thus suggesting that the information in the display is being processed in parallel unattendedly or pre-attentively.
However, if the target is composed of a conjunction of unique features, i.e. a conjoin search, then research shows that these may not be detected preattentively. Using the above examples, if a target is comprised for example, of a red circle set within distractors including blue circles and red squares, it is not possible to detect the red circle preattentively as all the distractors include one of the two unique features of the target.
Whilst the above example is based on a relatively simple visual scene, Enns and Rensink [1990] identified that targets given the appearance of being three-dimensional objects can also be detected preattentively. Thus, for example a target represented by a perspective view of a cube shaded to indicate illumination from above would be preattentively detectable amongst a plurality of distractor cubes shaded to imply illumination from a different direction. This illustrates an important principle in that the relatively complex, high-level concept of perceived three-dimensionality may be processed preattentively by the sub-conscious mind. In comparison, if the constituent elements of the above-described cubes are re-orientated to remove the apparent three dimensionality, subjects cannot preattentively detect targets which have been inverted for example. Additional experimentation by Brown et al [1992] confirms that it is the three-dimensional orientation characteristic that is preattentively detected. Nakaymyama and Silverman [1986] showed that motion and depth were preattentive characteristics and that furthermore, stereoscopic depth could be used to overcome the effects of conjoin. This reinforced the work done by Enns Rensink in suggesting that high-level information is conceptually being processed by the low-level visual system of the user. To test the effects of depth, subjects were tasked with detecting targets of different binocular disparity relative to the distractors. Results showed a constant response time irrespective of the increase in distractor numbers.
These experiments were followed by conjoin tasks whereby blue distractors were placed on a front plane whilst red distractors were located on a rear plane and the target was either red on the front plane or blue on the rear plane for stereo colour (SC) conjoin tests, whilst stereo and motion (SM) trials utilised distractors on the front plane moving up or on the back plane moving down with a target on either the front plane moving down or on the back plane moving up.
Results showed the response time for SC and SM trials were constant and below the 250 msec threshold regardless of the number of distractors. The trials involved conjoin as the target did not possess a feature unique to all the distractors. However, it appeared the observers were able to search each plane preattentively in turn without interference from distractors in another plane.
This research was further reinforced by Melton and Scharff [1998] in a series of experiments in which a search task consisting of locating an intermediate-sized target amongst large and small distractors tested the serial nature of the search whereby the target was embedded in the same plane as the distractors and the preattentive nature of the search whereby the target was placed in a separate depth plane to the distractors.
The relative influence of the total number of distractors present (regardless of their depth) verses the number of distractors present solely in the depth plane of the target was also investigated. The results showed a number of interesting features including the significant modification of the response time resulting from the target presence or absence. In the target absence trials, the reaction times of all the subjects displayed a direct correspondence to the number of distractors whilst the target present trials did not display any such dependency. Furthermore, it was found that the reaction times in instances where distractors were spread across multiple depths were faster than for distractors located in a single depth plane.
Consequently, the use of a plurality of depth/focal planes as a means of displaying information can enhance preattentive processing with enhanced reaction/assimilation times.
It is thus believed that a means of overcoming the above described drawbacks is available by harnessing the peripheral vision and subconscious perception of the reader (particularly in conjunction with multi focal plane displays) to assimilate additional information sources simultaneously with the process of conventional reading in order to enhance the speed and effectiveness of the whole reading/viewing process.
The benefits of the multi-layered viewing screens, in particular those utilising the technology described in the co-pending Patent Application Nos. NZ314566, NZ328074, NZ329130, PCT/NZ98/00098 and PCT/NZ99/00021 are especially germane to displays using liquid crystal displays (LCD).
There are two main types of Liquid Crystal Displays used in computer monitors, passive matrix and active matrix. Passive-matrix Liquid Crystal Displays use a simple grid to supply the charge to a particular pixel on the display. Creating the grid starts with two glass layers called substrates. One substrate is given columns and the other is given rows made from a transparent conductive material. This is usually indium tin oxide. The rows or columns are connected to integrated circuits that control when a charge is sent down a particular column or row. The liquid crystal material is sandwiched between the two glass substrates, and a polarizing film is added to the outer side of each substrate.
A pixel is defined as the smallest resolvable area of an image, either on a screen or stored in memory. Each pixel in a monochrome image has its own brightness, from 0 for black to the maximum value (e.g. 255 for an eight-bit pixel) for white. In a colour image, each pixel has its own brightness and colour, usually represented as a triple of red, green and blue intensities. To turn on a pixel, the integrated circuit sends a charge down the correct column of one substrate and a ground activated on the correct row of the other. The row and column intersect at the designated pixel and that delivers the voltage to untwist the liquid crystals at that pixel.
The passive matrix system has significant drawbacks, notably slow response time and imprecise voltage control. Response time refers to the Liquid Crystal Displays ability to refresh the image displayed. Imprecise voltage control hinders the passive matrix's ability to influence only one pixel at a time. When voltage is applied to untwist one pixel, the pixels around it also partially untwist, which makes images appear fuzzy and lacking in contrast.
Active-matrix Liquid Crystal Displays depend on thin film transistors (TFT). Thin film transistors are tiny switching transistors and capacitors. They are arranged in a matrix on a glass substrate. To address a particular pixel, the proper row is switched on, and then a charge is sent down the correct column. Since all of the other rows that the column intersects are turned off, only the capacitor at the designated pixel receives a charge. The capacitor is able to hold the charge until the next refresh cycle. And if the amount of voltage supplied to the crystal is carefully controlled, it can be made to untwist only enough to allow some light through. By doing this in very exact, very small increments, Liquid Crystal Displays can create a grey scale. Most displays today offer 256 levels of brightness per pixel.
A Liquid Crystal Display that can show colours must have three subpixels with red, green and blue colour filters to create each colour pixel. Through the careful control and variation of the voltage applied, the intensity of each subpixel can range over 256 shades. Combining the subpixel produces a possible palette of 16.8 million colours (256 shades of red×256 shades of green×256 shades of blue).
Liquid Crystal Displays employ several variations of liquid crystal technology, including super twisted nematics, dual scan twisted nematics, ferroelectric liquid crystal and surface stabilized ferroelectric liquid crystal. They can be lit using ambient light in which case they are termed as reflective, backlit and termed Transmissive, or a combination of backlit and reflective and called transflective. There are also emissive technologies such as Organic Light Emitting Diodes, and technologies which project an image directly onto the back of the retina which are addressed in the same manner as Liquid Crystal Displays. These devices are described hereafter as LCD panels
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is acknowledged that the term ‘comprise’ may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term ‘comprise’ shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term ‘comprised’ or ‘comprising’ is used in relation to one or more steps in a method or process.
It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.
Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.